1. Field of the Invention
The present invention relates to a method and an apparatus for creating a search information for searching digital data streams recorded on a recording medium and relates to a method and apparatus for searching requested data using the search information.
2. Description of the Related Art
In conventional analog television broadcasts, video signals are transmitted over the air or through cables after being AM or FM modulated. With the recent advance of digital technologies such as digital image compression or digital modulation/demodulation, standardization for digital television broadcast is in rapid progress. Based upon the Moving Picture Experts Group (MPEG) format, satellite and cable broadcasting industries are also moving towards digital broadcast.
Digital broadcast offers several advantages that its analog counterpart cannot provide. For example, digital broadcast is capable of providing services with far more improved video/audio quality, transmitting several different programs within a fixed bandwidth, and offering enhanced compatibility with digital communications media or digital storage media.
In digital broadcast, a plurality of programs encoded based upon the MPEG format are multiplexed into a single transport stream before transmitted. The transmitted transport stream is received by a set top box at the receiver and demultiplexed into original programs. If a program is chosen from among the demultiplexed programs, the chosen program is decoded by a decoder in the set top box and the original audio and video signals are retrieved. The retrieved audio and video signals can be presented by an A/V output apparatus, such as a TV.
It is also possible to record the received digital broadcast signals on a storage medium instead of directly outputting the received broadcast signals to A/V output devices. The stored digital broadcast signals can be edited and retrieved afterwards. For example, a digital data stream received by the set top box can be transmitted to a streamer, such as a digital video disk (DVD) recording apparatus, through communication interfaces like an IEEE-1394 serial bus and stored in the streamer. The stored digital data stream can be edited and transmitted back to the set top box so that the digital audio and video data can be presented.
For recording a received digital broadcast stream on a recording medium, it is necessary to develop schemes to organize the digital data stream on the recording medium and to create management information for rapid access to the recorded data stream.